RESUMO
Fucosyl-oligosaccharides are natural prebiotics that promote the growth of probiotics in human gut and stimulate the innate immune system. In this work, the release of α-lfucosidase by Lactobacillus rhamnosus GG, and the use of this enzyme for the synthesis of fucosyl-oligosaccharides were investigated. Since α-lfucosidase is a membrane-bound enzyme, its release from the cells was induced by addition of 4-nitrophenyl-α-l-fucopyranoside (pNP-Fuc). Enzyme activity associated with the cell was recovered at 78% of its total activity. Fucosyl-oligosaccharides where synthesized using α-l-fucosidase extract and pNP-Fuc as donor substrate, and D-lactose or D-lactulose as acceptor substrates, reaching a yield up to 25%. Fucosyllactose was obtained as a reaction product with D-lactose, and its composition was confirmed by mass spectrometry (MALDI-TOF MS). It is possible that the fucosyl-oligosaccharide synthesized in this study has biological functions similar to human milk oligosaccharides.
Assuntos
Lacticaseibacillus rhamnosus/enzimologia , Oligossacarídeos/biossíntese , alfa-L-Fucosidase/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Parede Celular/enzimologia , Cromatografia Líquida de Alta Pressão , Glicosídeos/química , Humanos , Espectrometria de Massas , Oligossacarídeos/química , Prebióticos , Especificidade por Substrato , alfa-L-Fucosidase/metabolismoRESUMO
Glycosylhydrolases of various origins were used to produce fucose-containing disaccharides with prebiotic potential using different donor substrates and L-fucose as the acceptor substrate. Eight different disaccharides were synthesized as follows: three ß-D-galactosyl-L-fucosides with glycosidase CloneZyme Gly-001-02 using D-lactose as a donor substrate, two with a structure similar to prebiotics; one ß-D-galactosyl-L-fucose with ß-D-galactosidase from Aspergillus oryzae using D-lactose as a substrate donor; and four α-D-glucosyl-L-fucosides with α-D-glucosidase from Saccharomyces cerevisiae using D-maltose as a donor substrate. All disaccharides were purified and hydrolyzed. In all cases, an L-fucose moiety was present, and it was confirmed for ß-D-galactosyl-L-fucose by mass spectrometry. High concentrations of L-fucose as the acceptor substrate enhanced the synthesis of the oligosaccharides in all cases. The three enzymes were able to synthesize fucose-containing disaccharides when L-fucose was used as the acceptor substrate, and the highest yield was 20% using ß-D-galactosidase from Aspergillus oryzae.
